On May 23, 2009, at 19:49, Philip Taylor wrote:
> * Use some other prefix-binding mechanism (in both XHTML in HTML)
> like prefix="t=... T=..." instead of xmlns:t="..." (breaking current
> implementations and deployed content, but avoiding the mess of
> parsing differences between XHTML and HTML).
>
> I can't think of any other solutions, so something is going to break
> no matter what is chosen.
* Use a mechanism other than CURIEs to turn attribute values into
absolute IRIs.
As it happens, the microdata to RDF conversion already has a mechanism
for mapping itemprop values to absolute IRIs without prefix-based
indirection. (And itemprop works nicely with Selectors, too, allowing
styling based on microdata, while Selectors don't support matching on
expanded CURIEs, so styling on RDFa would need to depend on the
prefixes that aren't supposed to be significant.) In fact, even RDFa
itself has a non-CURIE-based mapping from attribute values onto IRIs
for traditional rel tokens.
http://rdfa.info/wiki/Rdfa-in-html-issues currently has 12 issues.
Of these 8 pertain to mapping attribute values to URIs. Of those, 7
would be addressed by adopting the same mapping to IRI that itemprop
uses. (The remaining 1 issue--Mapping algorithm producing an invalid
IRI--is not an issue to the extent RDF processing doesn't really
process properties as IRIs but processes them as opaque strings.)
2 issues would be addressed if RDFa deferred to http://www.whatwg.org/specs/web-apps/current-work/#the-lang-and-xml
:lang-attributes
2 issues would be addressed if RDFa deferred to http://www.whatwg.org/specs/web-apps/current-work/#coercing-an-html-dom-into-an-infoset
--
Henri Sivonen
hsivonen@iki.fihttp://hsivonen.iki.fi/